This invention relates to unique elastomeric damping sheet geometry and design. Elastomeric materials are employed extensively in applications where shock and vibration must be minimized. Such applications include sports equipment, tools, automobiles, airplanes, and many other types of apparatus. It is also becoming increasingly important to minimize failures due to impact forces applied to electronic equipment, such as digital computers, especially when such equipment is employed in harsh, rugged environments.
Previously, various elastomeric materials have been used, or suggested for use, to provide shock and/or vibration damping, as stated in U.S. Pat. No. 5,766,720 issued in Jun. 16, 1998 to Yamagishi, et. al. These materials include natural rubbers and synthetic resins, such as polyvinylchlorides, polyurethane, polyamides, polystyrenes, copolymerized polyvinyl chlorides, and polyolefine synthetic rubbers, as well as synthetic materials such as urethane, EPDM, styrene-butadiene rubbers, nitrites, isoprene, chloroprenes, propylene, and silicones. The particular type of elastomeric material employed is not critical, but urethane material sold under the trademark Sorbothane(copyright) is currently employed. Suitable material is also sold by Aero E.A.R. Specialty Composites, as Isoloss VL. The registrant of the mark Sorbothane(copyright) for urethane material is the Hamilton Kent Manufacturing Company (Registration No. 1208333), Kent, Ohio 44240.
The elastomeric elements employed in the prior art were commonly formed into typical geometric 3D shapes, such as spheres, ;squares, right circular cylinders, cones, rectangles, and the like as illustrated in U.S. Pat. No. 5,776,720. These typical geometric shapes, however, did not satisfactorily eliminate the transfer of compressive forces through the damping device, and thus, did not minimize or eliminate shock and vibration to the degree accomplished by the devices of the invention.
In pending U.S. patent application Ser. No. 09/495,693 filed Feb. 1, 2001, now abandoned titled Elastomeric Damping Elements and Applications for Reducing Shock and Vibration, elastomeric damping elements of block shapes were disclosed. These elastomeric damping elements were formed with an elongated parallelogram cross-sectional shape, with a first flat mounting surface that extends parallel to the first flat mounting surface at a second end of the parallelogram cross-section, and is located so that a line drawn normal to one of the flat mounting surfaces will not intercept the other of the flat mounting surfaces. As an option, a space in the interior of the element could be provided, which is filled with particulate or fluid material that may be contained in a deformable package. Other materials that have different damping characteristics than the elastomeric sheet, may be poured into the interior of the element where they solidify.
The elastomeric sheet material of the present invention is formed of a continuous, flat elastomeric sheet or layer that has a plurality of channels that run through it, or, at least partially through it, such that the remaining material is formed with a plurality of structures that when viewed along, at least one, in cross-sectional continuing line of a general parallelogram shape. A method of correlating dimensions of elastomeric damping elements with applied forces to provide effective damping for given applications is also provided.